During IDEA’s annual District Energy Conference and Trade Show, in Indianapolis, USA, Juan Ontiveros, the ex-Chair of IDEA and the Executive Director of Utilities and Energy Management at the University of Texas at Austin, reported achieving 0.329kW/TR (for January 2010) at the district cooling scheme on campus. B Surendar of Climate Control Middle East caught up with him in Indianapolis to find out how. excerpts from the interview…
In your words, the university achieved 0.329kW/TR in January 2010. How did you manage to do so?
Where you start is important, and you start by having metering. Until you know the actual performance of each unit, each sub system and total, you cannot change. So you need to calibrate the instruments and meters. Twelve years ago, it was manual. It was, “Push this button and turn the valve.” I invested in automation and metering. Then, the question was, “Now that I have this, what do I do with the data?”
We need to look at overall performance and individual components and how to optimise the bottom-line. We started with just six data points on each chiller and turbine. We looked at opportunities at each data point, and we saw some obvious bottlenecks. We confronted several questions: “Do you have the right pipe size?” “Is there too much friction?” “Are your valves operating correctly?” “Is it too high or too low a flow?” “Is it because of an equipment problem?” “Is it a case of the pump not working or the valve being wrong?” “Is the pipe size wrong?”
Then, we did a lot of ‘what-if’ scenarios. We asked ourselves, “What happens to the total cost if you change a chiller?” In effect, we did cost-benefit analyses and lifecycle analyses. When you have everything instrumented, you have data. Then, you have to look at which data to use. We went for graphic tools to understand the data better, and it helped. If you don’t measure and model, you can’t improve.
How did you finance this vast study?
We took care of the easy things. It’s been a gradual process. The model also gives the operator a better understanding of how the total system works and not just the chillers or the pumps. When you have a model, you can see all the scenarios and make all the combinations. Our chiller stations run automatically. All the operator does is to start or stop the chillers.
The chiller station performance depends on many variables: weather, humidity, temperature and load. Also, if you have a VFD, the question was, “What speed should I have my chiller on?” The model controls all the variables and knows what the optimum performance curves are. It’s too many variables for humans to manage; that’s why you need a model. The model forces you to be honest. If I am losing on efficiency, maybe the weather is a factor.
The other side is people. I mean, people with knowledge, training and with a different mind-set. Earlier, it was: “I am an operator, and my job is to keep the car on the road. And as long as I do that, I am happy.” Today, the operator is also looking at reliability and efficiency.
You can get very high reliability by using redundant equipment. That’s the easy way. Now, the question is, “If I need only one pump, why run three?”
The maintenance people also have to change. From being a mechanic, you are working with digital controls. So we need this mindset. We use people that calibrate and make sure instrumentation is working as it should. So we have a whole new approach and highly skilled people.
If you go this method, you need less people. From 230 people, we are 179 people now. They are paid higher, because they bring higher skills.
When that mechanic or technician needed help, I created a middle manager. The guy is responsible for control and maintenance. The middle-managers are your future plant managers. It’s called succession management planning. If one of them is absent, the other can offer support.
Every mechanic has to complete 258 hours of training, and it is test-based. We want to raise the skill and knowledge level of people, and it makes you a strong organisation. We have smarter people. We empower people. My people also have a lot of authority. They call me now and say, ‘Hey, Juan, this is what we did.’ They don’t say, ‘Hey, Juan, what do we do?’
If they do make a mistake, it’s my mistake. If they make a success, it is their success. I will tell my boss that they are the reason for success. If there are repeated mistakes, we do incident analysis. We try to learn from the mistakes. We are good because of the culture we have. I want my people to take risks… calculated risks, to become more efficient. You have to encourage that. Once they don’t take risks, they are no longer efficient. They are just keeping the car on the road.
In short, it is all down to the right type of equipment and understanding the people. These are keys, which have helped us achieve the situation where we use the same amount of energy, though we are today cooling eight million square feet.
There is no silver bullet for our success. It’s work and transformational process, and I am proud of it. I come up with crazy ideas, but they have to do it. When you design a plant, you have to handle a peak, but most of the time, you operate at low demand. So the trick is how to operate at a peak and yet operate at low most of the times.